Uninitialized scalar field

The field will contain an arbitrary value left over from earlier computations. A scalar field is not initialized by the constructor
/src/mongo/db/repl/tenant_migration_donor_service.h:337: UNINIT_CTOR 121076 Class member declaration for "_isAtleastFCV52AtStart".
/src/mongo/db/repl/tenant_migration_donor_service.cpp:288: UNINIT_CTOR 121076 Non-static class member "_isAtleastFCV52AtStart" is not initialized in this constructor nor in any functions that it calls.